Mud-club

Hi all, I'm having difficulty getting into my maps section of my 3500, I've pressed the re-set and disconnected the battery but still get the same message which is that the device was not shut down correctly the last time, please tap the red X next time you turn off. Any suggestions as to how I can resolve this problem, I was hoping to use it tomorrow! I've connected it up to my laptop and the laptop doesn't see it, I've connected to device on the MM top task bar and still no luck!!